Die casting machine



March 13, 1934. D. RICHARDS DIE CASTING MACHINE Filed Oct. 2, 1933 5Sheets-Sheet 1 NEE INVEN 7'0/7 March 13, 1934. D RICHARDs 1,950,568

DIE CASTING MACHINE Filed Oct. 2, 1933 5 Sheets-Sheet 2 March 13, 1934.o. RICHARDS DIE CASTING MACHINE Filed Oct. 2, 1933 5 Sheets-Sheet 3 5Sheets-Sheet 4 HYVEHTOH March 13, 1934. o. RICHARDS DIE CASTING MACHINEFiled Oct. 2, 1933 Mam}?! H934}- n. RICHARDS 95495 1 DIE CASTING MACHINEFiled Oct. 2, 1935 5 Sheets-Shet 5 Patented Mar 13, 1934 UhiiilApplication Dctober 2, 1933, Serial No. 691,857 In Great BritainDecember 29, 193i 6 Claims.

This invention relates to die casting machines in which a carrier isused to transfer molten metal from the furnace and particularly toelectrically operated die casting machines, and has for its object tointroduce an improved construction of machine suitable for pressure diecasting in metals of low or high melting point, and particularlydesigned for speedy and accurate production of castings, and forelirmnating or reducing to a minimum the amount of surplus metal whichhas to be re-melted, and the use of tie rods between the die carriers.

According to this invention the metal in the metal carrier is completelysealed in its passage from the furnace to the die. For this purpose thelower portion of the metal in the furnace is transferred directly to ametal carrier that is provided with a movable cover plate and conveys ameasured quantity of metal in a sealed condition from the furnaceopening to a plunger for ejecting the metal into the die.

The machine when actuated electrically co1nprises a framework or bedhaving two raised ends of which one serves as a support for a solenoidactuated plunger and a stationary die carrier plate which is adjustablefor different lengths of metal carriers and may be water circulated forcooling purposes through a passage formed in the die carrier plate, andthe other serves as a support for a traversing die carrier plate and asolenoid that is used for closing its die against the die in thestationary die carrier plate. The body of the bed accommodates asolenoid for withdrawing the plunger from the die moving a metal carrierto the discharge orifice of an electrically heated furnace for receivinga charge of molten metal which is subsequently interposed between thedie in the stationary die carrier and the end of the plunger and iscompletely sealed in its passage from the furnace to the die so thatoxidation of the metal is prevented. The machine is constructed in suchmanner that it will perform one cycle of operations, and then stop, orrun u continuously at will. If desired compressed air 0 cylinders, orhydraulic power can be substituted for the solenoids.

In the accompanying drawings:

Fig. 1 is a side elevation of the furnace end of an electricallyactuated die casting machine constructed in accordance with thisinvention, and with the front side of the machine removed.

Fig. 1 is a detached View showing a telescopically arranged plunger.

55 Fig. 2 is a section, partly in elevation, of the movable die end ofthe machine substantially on line 2--2 of Fig. 3.

Figs. 3 and 4 are sections looking in the direction of the arrows 3 and4 in Fig. 1.

Fig. 5 is a plan of the furnace end of the machine.

Fig. 6 is a plan of part of Fig. 5 with the furnace and solenoidremoved.

Fig. '5 is a plan of he movable die end of the machine.

Fig. 8 is a section showing an enlarged view of the metal carrier andits cover plates, and

Figs. 9 and 1c are detached views of a trip mechanism for locating andreleasing the metal carrier plate.

A indicates the traversing die carrier plate, B the stationary diecarrier plate, C the plunger that is actuated by the solenoid (1 D thesolenoid for closing the die in the plate A against the die in the plateB, E the solenoid for withdrawing the plate A from the plate B, F themetal carrier, and G the furnace.

Pivoted to a casting a that is attached to the movable die carrier plateA is a pair of links a that are hinged by pins a to one pair of arms aof two bell crank levers that are pivotally mounted on lugs a on thecasing of the die closing solenoid D. The other pair of arms a of thebell crank levers are connected by links a and pins a, levers a a thatare rigidly fixed on a shaft H that extends transversely across themachine and is free to turn in bearings on the machine frame. Pivoted onthe pins a are two rods a the'free ends of which pass through holes incollars a on the pins a and enter holes in the latter. Screwed intothese holes are screw plugs 0, which form adjustable abutments for therods a to abut against just before the links a and arms a of the bellcrank levers, in which position the rods a bring the links a and arms ainto a straight line and give a final lock to the toggle joint made bythe links a and the arms a of the bell crank levers. Formed in a piecewith the arm a is another arm 6 that is attached by a rod 6 to one endof the core of the solenoid E that retracts the movable die carrierplate A from the stationary one B. Extending from the solenoid core atits other end is a rod 0 that is connected by a link 0 and pin 0 whichis formed with an extension 0 to a lever c fulcrumed on a shaft 0 thatextends transversely across the machine framework. The upper end of theaforesaid lever is forked and carries a pawl c that engages a snail camc" that is secured to the aforesaid shaft 0 upon which is also secured alever 0 The end of this lever is connected by a link 0 to a lever cwhich is fulcrumed at e and is connected at its other end by a pair oflinks 0 to the moving core of the plunger operating solenoid C The pawlc is provided with a tail piece 0 for engagement with an adjustable stop0 which is carried in a bracket 0 in the machine framework. The pawl cis provided with a tail piece e for engagement with an adjustable stop 0which is carried in a bracket 0 in the machine framework. The pawl c istripped at the end of the first half of the stroke of the solenoid E byengagement of the tail piece 0 with the stop 0 during the openingoperation of the die just prior to the raising of the metal carrier F.Situated parallel with the link 0 is a rod 1 slidably mounted inbearings f on the machine frame and provided with adjustable stops orcollars f f that engage with the extension 0 of the pin 0 The slidablymounted rod 1 is coupled by a link i to one arm of a bell crank lever,the other arm I of which is connected by a link I to a plate i to whichthe metal carrier F, Fig. 8 is attached. The metal plate f is free toslide in guides f fixed to or forming part of a plate I that comes flushwith the delivery outlet of the furnace G. The metal plate i is formedwith an aperture i corresponding in size to the furnace delivery outletand adapted to be moved into and out of line with the latter. Attachedto the metal plate f by screws f is the metal carrier F which comprisesa flanged tubular fitting, the bore of which corresponds in size to theaperture and registers with it. Attached to or forming part of the metalcarrier F are guiding surfaces i in which a cover plate i is slidablymounted and retained in intimate contact with the end of the metalcarrier by strong blade springs f mounted in recesses in the plate f. Atight joint is made between the working faces of the plates i F by meansof spring pressed rollers I" which bear against the metal carrier orplate f When the parts are in the position shown in Fig. 81 the metalcarrier F is charged with metal from the furnace G.

In operating the machine a switch (not shown) is first actuated tobringthe solenoid D into action for traversing the movable die carrier A andclosing the die (not shown). This movement of the movable die carrierpulls out the core of the solenoid E and causes the rod 0 and link 0 toturn the lever 0 until its pawl 0 passes the step of the snail cam c andthe extension 0 of the pin 0 on the lever c engages the stop f on therod 1 and retracts the latter thereby operating the connections f to fand the plate to lower the latter and metal carrier F to bring a chargeof molten metal opposite to the plunger C. During this movement thelower edge of the cover plate f strikes against the top of a tubularfitting b that is fixed in the stationary die carrier plate B with itsbore in line with the end of the plunger C. The movement of the coverplate is therefore arrested and the metal carrier continues to descenduntil it comes to rest in a pocket b in the tubular fitting b. The finalalignment of the metal carrier F with the tubular fitting b and plungerC is effected just before the die is closed and before the plunger C isactuated. This is effected by an adjustable stop J on the movable diecarrier plate coming into contact with one end of a rod 7' that isslidably mounted in the die carrier plate B and framework. The rod 7'then receives an endwise movement and turns a twoarmed lever 9' to lifta catch 1' thereon out of engagement with one arm 7' of a two-armedlever, the arm 9' of which is forked to embrace a spring controlledlocating pin 9' that is formed with a tapered end to enter a taperedhole 7' in the plate f and thereby correctly align the metal carrierwith the plunger C and tubular fitting b. Another switch (not shown) isnow operated to cause the plunger C to force the charge of molten metalthrough the carrier F into the dies. Towards the end of the plungermovement a projection 7 (Fig. l) on the lever 0 comes in contact with aprojection 7' (Fig. 9) on the arm 7' forcing the latter under the catch7 and withdrawing the locating pin 7 from the tapered hole 7' in theplate i A third switch (not shown) is now actuated to bring the dieopening solenoid E into action to open the discs. The core rod 0, link 0are moved out to turn the pawl carrying lever c to turn the shaft 0 toretract the plunger C until the tail piece 0 of the pawl 0 comes againstthe adjustable stop 0 to disengage the pawl from the snail cam 0''.Further outward movement of the core rod 0 causes the pin extension 0 toengage the collar 1 on the slidable rod 7 and actuate the latter toraise the metal carrier plate f to the furnace orifice ready for thenext cycle of operations through the connections f to 1. During theupward movement of the metal carrier F the plate I comes into contactwith a pin b and is moved back to close the end of the metal carrier F.The die closing solenoid D is adjustable along the machine framework tosuit various lengths, or thicknesses of dies. This adjustment iseffected by a centrally disposed screw (1 (Fig. '7) rotatable in theframework and engaging a tapped lug d on the solenoid casing. Otherscrews (2 pass through tapped bosses in the framework and are set upagainst lugs d on the solenoid casing in any of its adjusted positionsto receive the end thrust that is exerted during the die castingoperation, the position of the screws being maintained by lock nuts dAbutments b (Fig. 4) on the carrier plate B are provided to abut againstsimilar abutments on the raised portion of the framework to prevent theplate B from being forced backward by the pressure in the die. A handcontrol may be provided for traversing the movable die carrier plate Ain either direction by hand. In the example shown this is effected byfixing a toothed sector K on the shaft H and mounting a pinion k on ashaft k that is rotatable in bearings on the machine frame and providedwith a squared or other suitably shaped end for turning purposes. Ifdesired the shaft may be slidably mounted for taking the pinion 7c outof gear with the sector K. Instead of the plunger C being made in onepiece it may comprise two telescopic portions C C Fig. 1

normally held apart by springs C which keep their ends flush. When thesolenoid is started to force the metal from the metal carrier F into thetubular fitting b the outer member C is arrested by such fitting. Theinner telescopic member C continues to move forwards, and compresses thesprings C and forces the molten metal through the tubular fitting b intothe dies to apply the final pressure. By the use of a telescopic plungera solenoid of smaller power can be used to apply the same amount ofpressure to the molten metal in the die, a larger quantity of metal canbe carried in the metal carrier by increasing its bore without alteringthe length. Instead of the die carrier and cover plate moving with astraight line motion they may be mounted on pivoted arms and movethrough an arc of a circle. The switches for operating the solenoids maybe actuated separately by hand, or they may be controlled by cams tostart and stop the solenoids in sequence during the cycle of operationsand to cause the machine to run intermittently, or continuously. Thedies may be secured to their respective plates by clamping blocksarranged somewhat in the manner of the jaws of a chuck. The metalcarrier may be electrically heated to keep the charge of metal hotduring its transference from the furnace orifice to the die.

By constructing a machine in the manner described a clear working spaceis provided for manipulating the dies and tie rods which cross theopening between the two die carrier plates are dispensed with.

What I claim as my invention and desire to secure by Letters Patent inthe United States 1. In a die casting machine a plunger for ejectingmolten metal into a die, said plunger comprising two telescopic portionsso arranged that when the end of one telescopic portion comes to restagainst a stop, the other telescopic portion continues its movement andapplies the final pressure.

2. In an electrically operated die casting machine, a solenoid actuatedplunger, a stationary die carrier plate, a traversing die carrier plate,a solenoid for closing the die in the latter against the die in thestationary die carrier plate, a solenoid for retracting the traversingdie carrier plate from the stationary one, the said solenoid alsowithdrawing the plunger from the die and moving a metal carrier to thedischarge orifice of an electrically heated furnace for receiving acharge of molten metal which is subsequently interposed between the diein the stationary die carrier and the end of the plunger.

3. In a die casting machine, a die carrier plate, a melting furnace, acarrierfor molten metal movable between said furnace and die carrierplate for registry with the furnace outlet in one position and with thedie carrier plate inlet in another position, and means on said carrierfor closing the furnace outlet when the carrier moves to the die carrierplate inlet.

4. In a die casting machine, a melting furnace, a carrier for moltenmetal movable into registry with the furnace outlet to receive a chargetherefrom, a die carrier plate having an inlet, a movable closure onsaid metal carrier, means for moving said metal carrier into registrywith said die carrier plate inlet, and means for opening said movableclosure as the metal carrier moves into registry with the die carrierplate inlet.

5. In a die casting machine, a melting furnace, a carrier for moltenmetal movable into registry with the furnace outlet to receive a charge,a closure for said carrier, a die carrier plate having an inlet, meansfor moving said metal carrier into registry with the die carrier plateinlet, and means on said die carrier plate for opening the metal carrierclosure as the metal carrier moves into registry with the die carrierplate inlet.

6. In a die casting machine, melting means,

charge transfer movement, and said closing 11;:

means being operable to open position by contact with said die holdermeans.

DANIEL RICHARDS.

